An injection device (100) suitable for the delivery of a viscous medicament from a container (10) through a needle (16) disposed at the distal end of the container (10) is disclosed. The device comprises a housing (102), an advancing mechanism (190, 204, 230) operable to move the container (10) relative to the housing from a starting position in which the needle (16) is shrouded and an insertion position in which the needle (16) is exposed, and a stopper drive arrangement operable to move a stopper (22) towards the distal end of the container (10). The stopper drive arrangement comprises a drive body (240) arranged for axial movement with respect to the housing (102), a driveshaft (250) arranged for rotation with respect to the drive body (240), a plunger (202) arranged for axial movement with respect to the drive body (240) to move the stopper (22) upon rotation of the driveshaft (250), and drive means (290) arranged to rotate the driveshaft (250) upon activation of the stopper drive arrangement.